Merge branch 'tg/worktree-create-tracking' into maint
[git] / upload-pack.c
1 #include "cache.h"
2 #include "config.h"
3 #include "refs.h"
4 #include "pkt-line.h"
5 #include "sideband.h"
6 #include "tag.h"
7 #include "object.h"
8 #include "commit.h"
9 #include "exec_cmd.h"
10 #include "diff.h"
11 #include "revision.h"
12 #include "list-objects.h"
13 #include "run-command.h"
14 #include "connect.h"
15 #include "sigchain.h"
16 #include "version.h"
17 #include "string-list.h"
18 #include "parse-options.h"
19 #include "argv-array.h"
20 #include "prio-queue.h"
21 #include "protocol.h"
22
23 static const char * const upload_pack_usage[] = {
24         N_("git upload-pack [<options>] <dir>"),
25         NULL
26 };
27
28 /* Remember to update object flag allocation in object.h */
29 #define THEY_HAVE       (1u << 11)
30 #define OUR_REF         (1u << 12)
31 #define WANTED          (1u << 13)
32 #define COMMON_KNOWN    (1u << 14)
33 #define REACHABLE       (1u << 15)
34
35 #define SHALLOW         (1u << 16)
36 #define NOT_SHALLOW     (1u << 17)
37 #define CLIENT_SHALLOW  (1u << 18)
38 #define HIDDEN_REF      (1u << 19)
39
40 static timestamp_t oldest_have;
41
42 static int deepen_relative;
43 static int multi_ack;
44 static int no_done;
45 static int use_thin_pack, use_ofs_delta, use_include_tag;
46 static int no_progress, daemon_mode;
47 /* Allow specifying sha1 if it is a ref tip. */
48 #define ALLOW_TIP_SHA1  01
49 /* Allow request of a sha1 if it is reachable from a ref (possibly hidden ref). */
50 #define ALLOW_REACHABLE_SHA1    02
51 /* Allow request of any sha1. Implies ALLOW_TIP_SHA1 and ALLOW_REACHABLE_SHA1. */
52 #define ALLOW_ANY_SHA1  07
53 static unsigned int allow_unadvertised_object_request;
54 static int shallow_nr;
55 static struct object_array have_obj;
56 static struct object_array want_obj;
57 static struct object_array extra_edge_obj;
58 static unsigned int timeout;
59 static int keepalive = 5;
60 /* 0 for no sideband,
61  * otherwise maximum packet size (up to 65520 bytes).
62  */
63 static int use_sideband;
64 static int advertise_refs;
65 static int stateless_rpc;
66 static const char *pack_objects_hook;
67
68 static void reset_timeout(void)
69 {
70         alarm(timeout);
71 }
72
73 static void send_client_data(int fd, const char *data, ssize_t sz)
74 {
75         if (use_sideband) {
76                 send_sideband(1, fd, data, sz, use_sideband);
77                 return;
78         }
79         if (fd == 3)
80                 /* emergency quit */
81                 fd = 2;
82         if (fd == 2) {
83                 /* XXX: are we happy to lose stuff here? */
84                 xwrite(fd, data, sz);
85                 return;
86         }
87         write_or_die(fd, data, sz);
88 }
89
90 static int write_one_shallow(const struct commit_graft *graft, void *cb_data)
91 {
92         FILE *fp = cb_data;
93         if (graft->nr_parent == -1)
94                 fprintf(fp, "--shallow %s\n", oid_to_hex(&graft->oid));
95         return 0;
96 }
97
98 static void create_pack_file(void)
99 {
100         struct child_process pack_objects = CHILD_PROCESS_INIT;
101         char data[8193], progress[128];
102         char abort_msg[] = "aborting due to possible repository "
103                 "corruption on the remote side.";
104         int buffered = -1;
105         ssize_t sz;
106         int i;
107         FILE *pipe_fd;
108
109         if (!pack_objects_hook)
110                 pack_objects.git_cmd = 1;
111         else {
112                 argv_array_push(&pack_objects.args, pack_objects_hook);
113                 argv_array_push(&pack_objects.args, "git");
114                 pack_objects.use_shell = 1;
115         }
116
117         if (shallow_nr) {
118                 argv_array_push(&pack_objects.args, "--shallow-file");
119                 argv_array_push(&pack_objects.args, "");
120         }
121         argv_array_push(&pack_objects.args, "pack-objects");
122         argv_array_push(&pack_objects.args, "--revs");
123         if (use_thin_pack)
124                 argv_array_push(&pack_objects.args, "--thin");
125
126         argv_array_push(&pack_objects.args, "--stdout");
127         if (shallow_nr)
128                 argv_array_push(&pack_objects.args, "--shallow");
129         if (!no_progress)
130                 argv_array_push(&pack_objects.args, "--progress");
131         if (use_ofs_delta)
132                 argv_array_push(&pack_objects.args, "--delta-base-offset");
133         if (use_include_tag)
134                 argv_array_push(&pack_objects.args, "--include-tag");
135
136         pack_objects.in = -1;
137         pack_objects.out = -1;
138         pack_objects.err = -1;
139
140         if (start_command(&pack_objects))
141                 die("git upload-pack: unable to fork git-pack-objects");
142
143         pipe_fd = xfdopen(pack_objects.in, "w");
144
145         if (shallow_nr)
146                 for_each_commit_graft(write_one_shallow, pipe_fd);
147
148         for (i = 0; i < want_obj.nr; i++)
149                 fprintf(pipe_fd, "%s\n",
150                         oid_to_hex(&want_obj.objects[i].item->oid));
151         fprintf(pipe_fd, "--not\n");
152         for (i = 0; i < have_obj.nr; i++)
153                 fprintf(pipe_fd, "%s\n",
154                         oid_to_hex(&have_obj.objects[i].item->oid));
155         for (i = 0; i < extra_edge_obj.nr; i++)
156                 fprintf(pipe_fd, "%s\n",
157                         oid_to_hex(&extra_edge_obj.objects[i].item->oid));
158         fprintf(pipe_fd, "\n");
159         fflush(pipe_fd);
160         fclose(pipe_fd);
161
162         /* We read from pack_objects.err to capture stderr output for
163          * progress bar, and pack_objects.out to capture the pack data.
164          */
165
166         while (1) {
167                 struct pollfd pfd[2];
168                 int pe, pu, pollsize;
169                 int ret;
170
171                 reset_timeout();
172
173                 pollsize = 0;
174                 pe = pu = -1;
175
176                 if (0 <= pack_objects.out) {
177                         pfd[pollsize].fd = pack_objects.out;
178                         pfd[pollsize].events = POLLIN;
179                         pu = pollsize;
180                         pollsize++;
181                 }
182                 if (0 <= pack_objects.err) {
183                         pfd[pollsize].fd = pack_objects.err;
184                         pfd[pollsize].events = POLLIN;
185                         pe = pollsize;
186                         pollsize++;
187                 }
188
189                 if (!pollsize)
190                         break;
191
192                 ret = poll(pfd, pollsize,
193                         keepalive < 0 ? -1 : 1000 * keepalive);
194
195                 if (ret < 0) {
196                         if (errno != EINTR) {
197                                 error_errno("poll failed, resuming");
198                                 sleep(1);
199                         }
200                         continue;
201                 }
202                 if (0 <= pe && (pfd[pe].revents & (POLLIN|POLLHUP))) {
203                         /* Status ready; we ship that in the side-band
204                          * or dump to the standard error.
205                          */
206                         sz = xread(pack_objects.err, progress,
207                                   sizeof(progress));
208                         if (0 < sz)
209                                 send_client_data(2, progress, sz);
210                         else if (sz == 0) {
211                                 close(pack_objects.err);
212                                 pack_objects.err = -1;
213                         }
214                         else
215                                 goto fail;
216                         /* give priority to status messages */
217                         continue;
218                 }
219                 if (0 <= pu && (pfd[pu].revents & (POLLIN|POLLHUP))) {
220                         /* Data ready; we keep the last byte to ourselves
221                          * in case we detect broken rev-list, so that we
222                          * can leave the stream corrupted.  This is
223                          * unfortunate -- unpack-objects would happily
224                          * accept a valid packdata with trailing garbage,
225                          * so appending garbage after we pass all the
226                          * pack data is not good enough to signal
227                          * breakage to downstream.
228                          */
229                         char *cp = data;
230                         ssize_t outsz = 0;
231                         if (0 <= buffered) {
232                                 *cp++ = buffered;
233                                 outsz++;
234                         }
235                         sz = xread(pack_objects.out, cp,
236                                   sizeof(data) - outsz);
237                         if (0 < sz)
238                                 ;
239                         else if (sz == 0) {
240                                 close(pack_objects.out);
241                                 pack_objects.out = -1;
242                         }
243                         else
244                                 goto fail;
245                         sz += outsz;
246                         if (1 < sz) {
247                                 buffered = data[sz-1] & 0xFF;
248                                 sz--;
249                         }
250                         else
251                                 buffered = -1;
252                         send_client_data(1, data, sz);
253                 }
254
255                 /*
256                  * We hit the keepalive timeout without saying anything; send
257                  * an empty message on the data sideband just to let the other
258                  * side know we're still working on it, but don't have any data
259                  * yet.
260                  *
261                  * If we don't have a sideband channel, there's no room in the
262                  * protocol to say anything, so those clients are just out of
263                  * luck.
264                  */
265                 if (!ret && use_sideband) {
266                         static const char buf[] = "0005\1";
267                         write_or_die(1, buf, 5);
268                 }
269         }
270
271         if (finish_command(&pack_objects)) {
272                 error("git upload-pack: git-pack-objects died with error.");
273                 goto fail;
274         }
275
276         /* flush the data */
277         if (0 <= buffered) {
278                 data[0] = buffered;
279                 send_client_data(1, data, 1);
280                 fprintf(stderr, "flushed.\n");
281         }
282         if (use_sideband)
283                 packet_flush(1);
284         return;
285
286  fail:
287         send_client_data(3, abort_msg, sizeof(abort_msg));
288         die("git upload-pack: %s", abort_msg);
289 }
290
291 static int got_oid(const char *hex, struct object_id *oid)
292 {
293         struct object *o;
294         int we_knew_they_have = 0;
295
296         if (get_oid_hex(hex, oid))
297                 die("git upload-pack: expected SHA1 object, got '%s'", hex);
298         if (!has_object_file(oid))
299                 return -1;
300
301         o = parse_object(oid);
302         if (!o)
303                 die("oops (%s)", oid_to_hex(oid));
304         if (o->type == OBJ_COMMIT) {
305                 struct commit_list *parents;
306                 struct commit *commit = (struct commit *)o;
307                 if (o->flags & THEY_HAVE)
308                         we_knew_they_have = 1;
309                 else
310                         o->flags |= THEY_HAVE;
311                 if (!oldest_have || (commit->date < oldest_have))
312                         oldest_have = commit->date;
313                 for (parents = commit->parents;
314                      parents;
315                      parents = parents->next)
316                         parents->item->object.flags |= THEY_HAVE;
317         }
318         if (!we_knew_they_have) {
319                 add_object_array(o, NULL, &have_obj);
320                 return 1;
321         }
322         return 0;
323 }
324
325 static int reachable(struct commit *want)
326 {
327         struct prio_queue work = { compare_commits_by_commit_date };
328
329         prio_queue_put(&work, want);
330         while (work.nr) {
331                 struct commit_list *list;
332                 struct commit *commit = prio_queue_get(&work);
333
334                 if (commit->object.flags & THEY_HAVE) {
335                         want->object.flags |= COMMON_KNOWN;
336                         break;
337                 }
338                 if (!commit->object.parsed)
339                         parse_object(&commit->object.oid);
340                 if (commit->object.flags & REACHABLE)
341                         continue;
342                 commit->object.flags |= REACHABLE;
343                 if (commit->date < oldest_have)
344                         continue;
345                 for (list = commit->parents; list; list = list->next) {
346                         struct commit *parent = list->item;
347                         if (!(parent->object.flags & REACHABLE))
348                                 prio_queue_put(&work, parent);
349                 }
350         }
351         want->object.flags |= REACHABLE;
352         clear_commit_marks(want, REACHABLE);
353         clear_prio_queue(&work);
354         return (want->object.flags & COMMON_KNOWN);
355 }
356
357 static int ok_to_give_up(void)
358 {
359         int i;
360
361         if (!have_obj.nr)
362                 return 0;
363
364         for (i = 0; i < want_obj.nr; i++) {
365                 struct object *want = want_obj.objects[i].item;
366
367                 if (want->flags & COMMON_KNOWN)
368                         continue;
369                 want = deref_tag(want, "a want line", 0);
370                 if (!want || want->type != OBJ_COMMIT) {
371                         /* no way to tell if this is reachable by
372                          * looking at the ancestry chain alone, so
373                          * leave a note to ourselves not to worry about
374                          * this object anymore.
375                          */
376                         want_obj.objects[i].item->flags |= COMMON_KNOWN;
377                         continue;
378                 }
379                 if (!reachable((struct commit *)want))
380                         return 0;
381         }
382         return 1;
383 }
384
385 static int get_common_commits(void)
386 {
387         struct object_id oid;
388         char last_hex[GIT_MAX_HEXSZ + 1];
389         int got_common = 0;
390         int got_other = 0;
391         int sent_ready = 0;
392
393         save_commit_buffer = 0;
394
395         for (;;) {
396                 char *line = packet_read_line(0, NULL);
397                 const char *arg;
398
399                 reset_timeout();
400
401                 if (!line) {
402                         if (multi_ack == 2 && got_common
403                             && !got_other && ok_to_give_up()) {
404                                 sent_ready = 1;
405                                 packet_write_fmt(1, "ACK %s ready\n", last_hex);
406                         }
407                         if (have_obj.nr == 0 || multi_ack)
408                                 packet_write_fmt(1, "NAK\n");
409
410                         if (no_done && sent_ready) {
411                                 packet_write_fmt(1, "ACK %s\n", last_hex);
412                                 return 0;
413                         }
414                         if (stateless_rpc)
415                                 exit(0);
416                         got_common = 0;
417                         got_other = 0;
418                         continue;
419                 }
420                 if (skip_prefix(line, "have ", &arg)) {
421                         switch (got_oid(arg, &oid)) {
422                         case -1: /* they have what we do not */
423                                 got_other = 1;
424                                 if (multi_ack && ok_to_give_up()) {
425                                         const char *hex = oid_to_hex(&oid);
426                                         if (multi_ack == 2) {
427                                                 sent_ready = 1;
428                                                 packet_write_fmt(1, "ACK %s ready\n", hex);
429                                         } else
430                                                 packet_write_fmt(1, "ACK %s continue\n", hex);
431                                 }
432                                 break;
433                         default:
434                                 got_common = 1;
435                                 memcpy(last_hex, oid_to_hex(&oid), 41);
436                                 if (multi_ack == 2)
437                                         packet_write_fmt(1, "ACK %s common\n", last_hex);
438                                 else if (multi_ack)
439                                         packet_write_fmt(1, "ACK %s continue\n", last_hex);
440                                 else if (have_obj.nr == 1)
441                                         packet_write_fmt(1, "ACK %s\n", last_hex);
442                                 break;
443                         }
444                         continue;
445                 }
446                 if (!strcmp(line, "done")) {
447                         if (have_obj.nr > 0) {
448                                 if (multi_ack)
449                                         packet_write_fmt(1, "ACK %s\n", last_hex);
450                                 return 0;
451                         }
452                         packet_write_fmt(1, "NAK\n");
453                         return -1;
454                 }
455                 die("git upload-pack: expected SHA1 list, got '%s'", line);
456         }
457 }
458
459 static int is_our_ref(struct object *o)
460 {
461         int allow_hidden_ref = (allow_unadvertised_object_request &
462                         (ALLOW_TIP_SHA1 | ALLOW_REACHABLE_SHA1));
463         return o->flags & ((allow_hidden_ref ? HIDDEN_REF : 0) | OUR_REF);
464 }
465
466 /*
467  * on successful case, it's up to the caller to close cmd->out
468  */
469 static int do_reachable_revlist(struct child_process *cmd,
470                                 struct object_array *src,
471                                 struct object_array *reachable)
472 {
473         static const char *argv[] = {
474                 "rev-list", "--stdin", NULL,
475         };
476         struct object *o;
477         char namebuf[42]; /* ^ + SHA-1 + LF */
478         int i;
479
480         cmd->argv = argv;
481         cmd->git_cmd = 1;
482         cmd->no_stderr = 1;
483         cmd->in = -1;
484         cmd->out = -1;
485
486         /*
487          * If the next rev-list --stdin encounters an unknown commit,
488          * it terminates, which will cause SIGPIPE in the write loop
489          * below.
490          */
491         sigchain_push(SIGPIPE, SIG_IGN);
492
493         if (start_command(cmd))
494                 goto error;
495
496         namebuf[0] = '^';
497         namebuf[GIT_SHA1_HEXSZ + 1] = '\n';
498         for (i = get_max_object_index(); 0 < i; ) {
499                 o = get_indexed_object(--i);
500                 if (!o)
501                         continue;
502                 if (reachable && o->type == OBJ_COMMIT)
503                         o->flags &= ~TMP_MARK;
504                 if (!is_our_ref(o))
505                         continue;
506                 memcpy(namebuf + 1, oid_to_hex(&o->oid), GIT_SHA1_HEXSZ);
507                 if (write_in_full(cmd->in, namebuf, GIT_SHA1_HEXSZ + 2) < 0)
508                         goto error;
509         }
510         namebuf[GIT_SHA1_HEXSZ] = '\n';
511         for (i = 0; i < src->nr; i++) {
512                 o = src->objects[i].item;
513                 if (is_our_ref(o)) {
514                         if (reachable)
515                                 add_object_array(o, NULL, reachable);
516                         continue;
517                 }
518                 if (reachable && o->type == OBJ_COMMIT)
519                         o->flags |= TMP_MARK;
520                 memcpy(namebuf, oid_to_hex(&o->oid), GIT_SHA1_HEXSZ);
521                 if (write_in_full(cmd->in, namebuf, GIT_SHA1_HEXSZ + 1) < 0)
522                         goto error;
523         }
524         close(cmd->in);
525         cmd->in = -1;
526         sigchain_pop(SIGPIPE);
527
528         return 0;
529
530 error:
531         sigchain_pop(SIGPIPE);
532
533         if (cmd->in >= 0)
534                 close(cmd->in);
535         if (cmd->out >= 0)
536                 close(cmd->out);
537         return -1;
538 }
539
540 static int get_reachable_list(struct object_array *src,
541                               struct object_array *reachable)
542 {
543         struct child_process cmd = CHILD_PROCESS_INIT;
544         int i;
545         struct object *o;
546         char namebuf[42]; /* ^ + SHA-1 + LF */
547
548         if (do_reachable_revlist(&cmd, src, reachable) < 0)
549                 return -1;
550
551         while ((i = read_in_full(cmd.out, namebuf, 41)) == 41) {
552                 struct object_id sha1;
553
554                 if (namebuf[40] != '\n' || get_oid_hex(namebuf, &sha1))
555                         break;
556
557                 o = lookup_object(sha1.hash);
558                 if (o && o->type == OBJ_COMMIT) {
559                         o->flags &= ~TMP_MARK;
560                 }
561         }
562         for (i = get_max_object_index(); 0 < i; i--) {
563                 o = get_indexed_object(i - 1);
564                 if (o && o->type == OBJ_COMMIT &&
565                     (o->flags & TMP_MARK)) {
566                         add_object_array(o, NULL, reachable);
567                                 o->flags &= ~TMP_MARK;
568                 }
569         }
570         close(cmd.out);
571
572         if (finish_command(&cmd))
573                 return -1;
574
575         return 0;
576 }
577
578 static int has_unreachable(struct object_array *src)
579 {
580         struct child_process cmd = CHILD_PROCESS_INIT;
581         char buf[1];
582         int i;
583
584         if (do_reachable_revlist(&cmd, src, NULL) < 0)
585                 return 1;
586
587         /*
588          * The commits out of the rev-list are not ancestors of
589          * our ref.
590          */
591         i = read_in_full(cmd.out, buf, 1);
592         if (i)
593                 goto error;
594         close(cmd.out);
595         cmd.out = -1;
596
597         /*
598          * rev-list may have died by encountering a bad commit
599          * in the history, in which case we do want to bail out
600          * even when it showed no commit.
601          */
602         if (finish_command(&cmd))
603                 goto error;
604
605         /* All the non-tip ones are ancestors of what we advertised */
606         return 0;
607
608 error:
609         sigchain_pop(SIGPIPE);
610         if (cmd.out >= 0)
611                 close(cmd.out);
612         return 1;
613 }
614
615 static void check_non_tip(void)
616 {
617         int i;
618
619         /*
620          * In the normal in-process case without
621          * uploadpack.allowReachableSHA1InWant,
622          * non-tip requests can never happen.
623          */
624         if (!stateless_rpc && !(allow_unadvertised_object_request & ALLOW_REACHABLE_SHA1))
625                 goto error;
626         if (!has_unreachable(&want_obj))
627                 /* All the non-tip ones are ancestors of what we advertised */
628                 return;
629
630 error:
631         /* Pick one of them (we know there at least is one) */
632         for (i = 0; i < want_obj.nr; i++) {
633                 struct object *o = want_obj.objects[i].item;
634                 if (!is_our_ref(o))
635                         die("git upload-pack: not our ref %s",
636                             oid_to_hex(&o->oid));
637         }
638 }
639
640 static void send_shallow(struct commit_list *result)
641 {
642         while (result) {
643                 struct object *object = &result->item->object;
644                 if (!(object->flags & (CLIENT_SHALLOW|NOT_SHALLOW))) {
645                         packet_write_fmt(1, "shallow %s",
646                                          oid_to_hex(&object->oid));
647                         register_shallow(&object->oid);
648                         shallow_nr++;
649                 }
650                 result = result->next;
651         }
652 }
653
654 static void send_unshallow(const struct object_array *shallows)
655 {
656         int i;
657
658         for (i = 0; i < shallows->nr; i++) {
659                 struct object *object = shallows->objects[i].item;
660                 if (object->flags & NOT_SHALLOW) {
661                         struct commit_list *parents;
662                         packet_write_fmt(1, "unshallow %s",
663                                          oid_to_hex(&object->oid));
664                         object->flags &= ~CLIENT_SHALLOW;
665                         /*
666                          * We want to _register_ "object" as shallow, but we
667                          * also need to traverse object's parents to deepen a
668                          * shallow clone. Unregister it for now so we can
669                          * parse and add the parents to the want list, then
670                          * re-register it.
671                          */
672                         unregister_shallow(&object->oid);
673                         object->parsed = 0;
674                         parse_commit_or_die((struct commit *)object);
675                         parents = ((struct commit *)object)->parents;
676                         while (parents) {
677                                 add_object_array(&parents->item->object,
678                                                  NULL, &want_obj);
679                                 parents = parents->next;
680                         }
681                         add_object_array(object, NULL, &extra_edge_obj);
682                 }
683                 /* make sure commit traversal conforms to client */
684                 register_shallow(&object->oid);
685         }
686 }
687
688 static void deepen(int depth, int deepen_relative,
689                    struct object_array *shallows)
690 {
691         if (depth == INFINITE_DEPTH && !is_repository_shallow()) {
692                 int i;
693
694                 for (i = 0; i < shallows->nr; i++) {
695                         struct object *object = shallows->objects[i].item;
696                         object->flags |= NOT_SHALLOW;
697                 }
698         } else if (deepen_relative) {
699                 struct object_array reachable_shallows = OBJECT_ARRAY_INIT;
700                 struct commit_list *result;
701
702                 get_reachable_list(shallows, &reachable_shallows);
703                 result = get_shallow_commits(&reachable_shallows,
704                                              depth + 1,
705                                              SHALLOW, NOT_SHALLOW);
706                 send_shallow(result);
707                 free_commit_list(result);
708                 object_array_clear(&reachable_shallows);
709         } else {
710                 struct commit_list *result;
711
712                 result = get_shallow_commits(&want_obj, depth,
713                                              SHALLOW, NOT_SHALLOW);
714                 send_shallow(result);
715                 free_commit_list(result);
716         }
717
718         send_unshallow(shallows);
719         packet_flush(1);
720 }
721
722 static void deepen_by_rev_list(int ac, const char **av,
723                                struct object_array *shallows)
724 {
725         struct commit_list *result;
726
727         result = get_shallow_commits_by_rev_list(ac, av, SHALLOW, NOT_SHALLOW);
728         send_shallow(result);
729         free_commit_list(result);
730         send_unshallow(shallows);
731         packet_flush(1);
732 }
733
734 static void receive_needs(void)
735 {
736         struct object_array shallows = OBJECT_ARRAY_INIT;
737         struct string_list deepen_not = STRING_LIST_INIT_DUP;
738         int depth = 0;
739         int has_non_tip = 0;
740         timestamp_t deepen_since = 0;
741         int deepen_rev_list = 0;
742
743         shallow_nr = 0;
744         for (;;) {
745                 struct object *o;
746                 const char *features;
747                 struct object_id oid_buf;
748                 char *line = packet_read_line(0, NULL);
749                 const char *arg;
750
751                 reset_timeout();
752                 if (!line)
753                         break;
754
755                 if (skip_prefix(line, "shallow ", &arg)) {
756                         struct object_id oid;
757                         struct object *object;
758                         if (get_oid_hex(arg, &oid))
759                                 die("invalid shallow line: %s", line);
760                         object = parse_object(&oid);
761                         if (!object)
762                                 continue;
763                         if (object->type != OBJ_COMMIT)
764                                 die("invalid shallow object %s", oid_to_hex(&oid));
765                         if (!(object->flags & CLIENT_SHALLOW)) {
766                                 object->flags |= CLIENT_SHALLOW;
767                                 add_object_array(object, NULL, &shallows);
768                         }
769                         continue;
770                 }
771                 if (skip_prefix(line, "deepen ", &arg)) {
772                         char *end = NULL;
773                         depth = strtol(arg, &end, 0);
774                         if (!end || *end || depth <= 0)
775                                 die("Invalid deepen: %s", line);
776                         continue;
777                 }
778                 if (skip_prefix(line, "deepen-since ", &arg)) {
779                         char *end = NULL;
780                         deepen_since = parse_timestamp(arg, &end, 0);
781                         if (!end || *end || !deepen_since ||
782                             /* revisions.c's max_age -1 is special */
783                             deepen_since == -1)
784                                 die("Invalid deepen-since: %s", line);
785                         deepen_rev_list = 1;
786                         continue;
787                 }
788                 if (skip_prefix(line, "deepen-not ", &arg)) {
789                         char *ref = NULL;
790                         struct object_id oid;
791                         if (expand_ref(arg, strlen(arg), &oid, &ref) != 1)
792                                 die("git upload-pack: ambiguous deepen-not: %s", line);
793                         string_list_append(&deepen_not, ref);
794                         free(ref);
795                         deepen_rev_list = 1;
796                         continue;
797                 }
798                 if (!skip_prefix(line, "want ", &arg) ||
799                     get_oid_hex(arg, &oid_buf))
800                         die("git upload-pack: protocol error, "
801                             "expected to get sha, not '%s'", line);
802
803                 features = arg + 40;
804
805                 if (parse_feature_request(features, "deepen-relative"))
806                         deepen_relative = 1;
807                 if (parse_feature_request(features, "multi_ack_detailed"))
808                         multi_ack = 2;
809                 else if (parse_feature_request(features, "multi_ack"))
810                         multi_ack = 1;
811                 if (parse_feature_request(features, "no-done"))
812                         no_done = 1;
813                 if (parse_feature_request(features, "thin-pack"))
814                         use_thin_pack = 1;
815                 if (parse_feature_request(features, "ofs-delta"))
816                         use_ofs_delta = 1;
817                 if (parse_feature_request(features, "side-band-64k"))
818                         use_sideband = LARGE_PACKET_MAX;
819                 else if (parse_feature_request(features, "side-band"))
820                         use_sideband = DEFAULT_PACKET_MAX;
821                 if (parse_feature_request(features, "no-progress"))
822                         no_progress = 1;
823                 if (parse_feature_request(features, "include-tag"))
824                         use_include_tag = 1;
825
826                 o = parse_object(&oid_buf);
827                 if (!o) {
828                         packet_write_fmt(1,
829                                          "ERR upload-pack: not our ref %s",
830                                          oid_to_hex(&oid_buf));
831                         die("git upload-pack: not our ref %s",
832                             oid_to_hex(&oid_buf));
833                 }
834                 if (!(o->flags & WANTED)) {
835                         o->flags |= WANTED;
836                         if (!((allow_unadvertised_object_request & ALLOW_ANY_SHA1) == ALLOW_ANY_SHA1
837                               || is_our_ref(o)))
838                                 has_non_tip = 1;
839                         add_object_array(o, NULL, &want_obj);
840                 }
841         }
842
843         /*
844          * We have sent all our refs already, and the other end
845          * should have chosen out of them. When we are operating
846          * in the stateless RPC mode, however, their choice may
847          * have been based on the set of older refs advertised
848          * by another process that handled the initial request.
849          */
850         if (has_non_tip)
851                 check_non_tip();
852
853         if (!use_sideband && daemon_mode)
854                 no_progress = 1;
855
856         if (depth == 0 && !deepen_rev_list && shallows.nr == 0)
857                 return;
858         if (depth > 0 && deepen_rev_list)
859                 die("git upload-pack: deepen and deepen-since (or deepen-not) cannot be used together");
860         if (depth > 0)
861                 deepen(depth, deepen_relative, &shallows);
862         else if (deepen_rev_list) {
863                 struct argv_array av = ARGV_ARRAY_INIT;
864                 int i;
865
866                 argv_array_push(&av, "rev-list");
867                 if (deepen_since)
868                         argv_array_pushf(&av, "--max-age=%"PRItime, deepen_since);
869                 if (deepen_not.nr) {
870                         argv_array_push(&av, "--not");
871                         for (i = 0; i < deepen_not.nr; i++) {
872                                 struct string_list_item *s = deepen_not.items + i;
873                                 argv_array_push(&av, s->string);
874                         }
875                         argv_array_push(&av, "--not");
876                 }
877                 for (i = 0; i < want_obj.nr; i++) {
878                         struct object *o = want_obj.objects[i].item;
879                         argv_array_push(&av, oid_to_hex(&o->oid));
880                 }
881                 deepen_by_rev_list(av.argc, av.argv, &shallows);
882                 argv_array_clear(&av);
883         }
884         else
885                 if (shallows.nr > 0) {
886                         int i;
887                         for (i = 0; i < shallows.nr; i++)
888                                 register_shallow(&shallows.objects[i].item->oid);
889                 }
890
891         shallow_nr += shallows.nr;
892         object_array_clear(&shallows);
893 }
894
895 /* return non-zero if the ref is hidden, otherwise 0 */
896 static int mark_our_ref(const char *refname, const char *refname_full,
897                         const struct object_id *oid)
898 {
899         struct object *o = lookup_unknown_object(oid->hash);
900
901         if (ref_is_hidden(refname, refname_full)) {
902                 o->flags |= HIDDEN_REF;
903                 return 1;
904         }
905         o->flags |= OUR_REF;
906         return 0;
907 }
908
909 static int check_ref(const char *refname_full, const struct object_id *oid,
910                      int flag, void *cb_data)
911 {
912         const char *refname = strip_namespace(refname_full);
913
914         mark_our_ref(refname, refname_full, oid);
915         return 0;
916 }
917
918 static void format_symref_info(struct strbuf *buf, struct string_list *symref)
919 {
920         struct string_list_item *item;
921
922         if (!symref->nr)
923                 return;
924         for_each_string_list_item(item, symref)
925                 strbuf_addf(buf, " symref=%s:%s", item->string, (char *)item->util);
926 }
927
928 static int send_ref(const char *refname, const struct object_id *oid,
929                     int flag, void *cb_data)
930 {
931         static const char *capabilities = "multi_ack thin-pack side-band"
932                 " side-band-64k ofs-delta shallow deepen-since deepen-not"
933                 " deepen-relative no-progress include-tag multi_ack_detailed";
934         const char *refname_nons = strip_namespace(refname);
935         struct object_id peeled;
936
937         if (mark_our_ref(refname_nons, refname, oid))
938                 return 0;
939
940         if (capabilities) {
941                 struct strbuf symref_info = STRBUF_INIT;
942
943                 format_symref_info(&symref_info, cb_data);
944                 packet_write_fmt(1, "%s %s%c%s%s%s%s%s agent=%s\n",
945                              oid_to_hex(oid), refname_nons,
946                              0, capabilities,
947                              (allow_unadvertised_object_request & ALLOW_TIP_SHA1) ?
948                                      " allow-tip-sha1-in-want" : "",
949                              (allow_unadvertised_object_request & ALLOW_REACHABLE_SHA1) ?
950                                      " allow-reachable-sha1-in-want" : "",
951                              stateless_rpc ? " no-done" : "",
952                              symref_info.buf,
953                              git_user_agent_sanitized());
954                 strbuf_release(&symref_info);
955         } else {
956                 packet_write_fmt(1, "%s %s\n", oid_to_hex(oid), refname_nons);
957         }
958         capabilities = NULL;
959         if (!peel_ref(refname, &peeled))
960                 packet_write_fmt(1, "%s %s^{}\n", oid_to_hex(&peeled), refname_nons);
961         return 0;
962 }
963
964 static int find_symref(const char *refname, const struct object_id *oid,
965                        int flag, void *cb_data)
966 {
967         const char *symref_target;
968         struct string_list_item *item;
969
970         if ((flag & REF_ISSYMREF) == 0)
971                 return 0;
972         symref_target = resolve_ref_unsafe(refname, 0, NULL, &flag);
973         if (!symref_target || (flag & REF_ISSYMREF) == 0)
974                 die("'%s' is a symref but it is not?", refname);
975         item = string_list_append(cb_data, refname);
976         item->util = xstrdup(symref_target);
977         return 0;
978 }
979
980 static void upload_pack(void)
981 {
982         struct string_list symref = STRING_LIST_INIT_DUP;
983
984         head_ref_namespaced(find_symref, &symref);
985
986         if (advertise_refs || !stateless_rpc) {
987                 reset_timeout();
988                 head_ref_namespaced(send_ref, &symref);
989                 for_each_namespaced_ref(send_ref, &symref);
990                 advertise_shallow_grafts(1);
991                 packet_flush(1);
992         } else {
993                 head_ref_namespaced(check_ref, NULL);
994                 for_each_namespaced_ref(check_ref, NULL);
995         }
996         string_list_clear(&symref, 1);
997         if (advertise_refs)
998                 return;
999
1000         receive_needs();
1001         if (want_obj.nr) {
1002                 get_common_commits();
1003                 create_pack_file();
1004         }
1005 }
1006
1007 static int upload_pack_config(const char *var, const char *value, void *unused)
1008 {
1009         if (!strcmp("uploadpack.allowtipsha1inwant", var)) {
1010                 if (git_config_bool(var, value))
1011                         allow_unadvertised_object_request |= ALLOW_TIP_SHA1;
1012                 else
1013                         allow_unadvertised_object_request &= ~ALLOW_TIP_SHA1;
1014         } else if (!strcmp("uploadpack.allowreachablesha1inwant", var)) {
1015                 if (git_config_bool(var, value))
1016                         allow_unadvertised_object_request |= ALLOW_REACHABLE_SHA1;
1017                 else
1018                         allow_unadvertised_object_request &= ~ALLOW_REACHABLE_SHA1;
1019         } else if (!strcmp("uploadpack.allowanysha1inwant", var)) {
1020                 if (git_config_bool(var, value))
1021                         allow_unadvertised_object_request |= ALLOW_ANY_SHA1;
1022                 else
1023                         allow_unadvertised_object_request &= ~ALLOW_ANY_SHA1;
1024         } else if (!strcmp("uploadpack.keepalive", var)) {
1025                 keepalive = git_config_int(var, value);
1026                 if (!keepalive)
1027                         keepalive = -1;
1028         } else if (current_config_scope() != CONFIG_SCOPE_REPO) {
1029                 if (!strcmp("uploadpack.packobjectshook", var))
1030                         return git_config_string(&pack_objects_hook, var, value);
1031         }
1032         return parse_hide_refs_config(var, value, "uploadpack");
1033 }
1034
1035 int cmd_main(int argc, const char **argv)
1036 {
1037         const char *dir;
1038         int strict = 0;
1039         struct option options[] = {
1040                 OPT_BOOL(0, "stateless-rpc", &stateless_rpc,
1041                          N_("quit after a single request/response exchange")),
1042                 OPT_BOOL(0, "advertise-refs", &advertise_refs,
1043                          N_("exit immediately after initial ref advertisement")),
1044                 OPT_BOOL(0, "strict", &strict,
1045                          N_("do not try <directory>/.git/ if <directory> is no Git directory")),
1046                 OPT_INTEGER(0, "timeout", &timeout,
1047                             N_("interrupt transfer after <n> seconds of inactivity")),
1048                 OPT_END()
1049         };
1050
1051         packet_trace_identity("upload-pack");
1052         check_replace_refs = 0;
1053
1054         argc = parse_options(argc, argv, NULL, options, upload_pack_usage, 0);
1055
1056         if (argc != 1)
1057                 usage_with_options(upload_pack_usage, options);
1058
1059         if (timeout)
1060                 daemon_mode = 1;
1061
1062         setup_path();
1063
1064         dir = argv[0];
1065
1066         if (!enter_repo(dir, strict))
1067                 die("'%s' does not appear to be a git repository", dir);
1068
1069         git_config(upload_pack_config, NULL);
1070
1071         switch (determine_protocol_version_server()) {
1072         case protocol_v1:
1073                 /*
1074                  * v1 is just the original protocol with a version string,
1075                  * so just fall through after writing the version string.
1076                  */
1077                 if (advertise_refs || !stateless_rpc)
1078                         packet_write_fmt(1, "version 1\n");
1079
1080                 /* fallthrough */
1081         case protocol_v0:
1082                 upload_pack();
1083                 break;
1084         case protocol_unknown_version:
1085                 BUG("unknown protocol version");
1086         }
1087
1088         return 0;
1089 }